/*
 * Copyright (C) 2022  即时通讯网(52im.net) & Jack Jiang.
 * The MobileIMSDK v6.1 Project.
 * All rights reserved.
 *
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 *
 * "即时通讯网(52im.net) - 即时通讯开发者社区!" 推荐开源工程。
 *
 * QoS4SendDaemonRoot.java at 2022-7-12 16:35:57, code by Jack Jiang.
 */
package com.dx.mobileimsdk.server.qos;

import com.dx.mobileimsdk.server.ServerLauncher;
import com.dx.mobileimsdk.server.network.MBObserver;
import com.dx.mobileimsdk.server.protocal.Protocal;
import com.dx.mobileimsdk.server.utils.LocalSendHelper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.Map.Entry;
import java.util.Timer;
import java.util.TimerTask;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.ConcurrentSkipListMap;

public class QoS4SendDaemonRoot {
    private static Logger logger = LoggerFactory.getLogger(QoS4SendDaemonRoot.class);

    private boolean DEBUG = false;
    private ServerLauncher serverLauncher = null;
    private ConcurrentSkipListMap<String, Protocal> sentMessages = new ConcurrentSkipListMap<String, Protocal>();
    private ConcurrentMap<String, Long> sendMessagesTimestamp = new ConcurrentHashMap<String, Long>();
    private int CHECH_INTERVAL = 5000;
    private int MESSAGES_JUST$NOW_TIME = 2 * 1000;
    private int QOS_TRY_COUNT = 1;
    private boolean _excuting = false;
    private Timer timer = null;
    private String debugTag = "";

    public QoS4SendDaemonRoot(int CHECH_INTERVAL
            , int MESSAGES_JUST$NOW_TIME
            , int QOS_TRY_COUNT
            , boolean DEBUG, String debugTag) {
        if (CHECH_INTERVAL > 0)
            this.CHECH_INTERVAL = CHECH_INTERVAL;
        if (MESSAGES_JUST$NOW_TIME > 0)
            this.MESSAGES_JUST$NOW_TIME = MESSAGES_JUST$NOW_TIME;
        if (QOS_TRY_COUNT >= 0)
            this.QOS_TRY_COUNT = QOS_TRY_COUNT;
        this.DEBUG = DEBUG;
        this.debugTag = debugTag;
    }

    private void doTaskOnece() {
        if (!_excuting) {
            ArrayList<Protocal> lostMessages = new ArrayList<Protocal>();
            _excuting = true;
            try {
                if (DEBUG && sentMessages.size() > 0)
                    logger.debug("【IMCORE" + this.debugTag + "】【QoS发送方】====== 消息发送质量保证线程运行中, 当前需要处理的列表长度为" + sentMessages.size() + "...");

                //** 遍历HashMap方法二（在大数据量情况下，方法二的性能要5倍优于方法一）
                Iterator<Entry<String, Protocal>> entryIt = sentMessages.entrySet().iterator();
                while (entryIt.hasNext()) {
                    Entry<String, Protocal> entry = entryIt.next();
                    String key = entry.getKey();
                    final Protocal p = entry.getValue();

                    if (p != null && p.isQoS()) {
                        if (p.getRetryCount() >= QOS_TRY_COUNT) {
                            if (DEBUG)
                                logger.debug("【IMCORE" + this.debugTag + "】【QoS发送方】指纹为" + p.getFp()
                                        + "的消息包重传次数已达" + p.getRetryCount() + "(最多" + QOS_TRY_COUNT + "次)上限，将判定为丢包！");

                            lostMessages.add((Protocal) p.clone());
                            remove(p.getFp());
                        } else {
                            //### 2015104 Bug Fix: 解决了无线网络延较大时，刚刚发出的消息在其应答包还在途中时被错误地进行重传
                            Long sendMessageTimestamp = sendMessagesTimestamp.get(key);
                            long delta = System.currentTimeMillis() - (sendMessageTimestamp == null ? 0 : sendMessageTimestamp);
                            if (delta <= MESSAGES_JUST$NOW_TIME) {
                                if (DEBUG)
                                    logger.warn("【IMCORE" + this.debugTag + "】【QoS发送方】指纹为" + key + "的包距\"刚刚\"发出才" + delta
                                            + "ms(<=" + MESSAGES_JUST$NOW_TIME + "ms将被认定是\"刚刚\"), 本次不需要重传哦.");
                            }
                            //### 2015103 Bug Fix END
                            else {
                                MBObserver sendResultObserver = new MBObserver() {
                                    @Override
                                    public void update(boolean sendOK, Object extraObj) {
                                        if (sendOK) {
                                            if (DEBUG) {
                                                logger.debug("【IMCORE" + debugTag + "】【QoS发送方】指纹为" + p.getFp()
                                                        + "的消息包已成功进行重传，此次之后重传次数已达"
                                                        + p.getRetryCount() + "(最多" + QOS_TRY_COUNT + "次).");
                                            }
                                        } else {
                                            if (DEBUG) {
                                                logger.warn("【IMCORE" + debugTag + "】【QoS发送方】指纹为" + p.getFp()
                                                        + "的消息包重传失败，它的重传次数之前已累计为"
                                                        + p.getRetryCount() + "(最多" + QOS_TRY_COUNT + "次).");
                                            }
                                        }
                                    }
                                };

                                LocalSendHelper.sendData(p, sendResultObserver);
                                p.increaseRetryCount();
                            }
                        }
                    } else {
                        remove(key);
                    }
                }
            } catch (Exception eee) {
                if (DEBUG)
                    logger.warn("【IMCORE" + this.debugTag + "】【QoS发送方】消息发送质量保证线程运行时发生异常," + eee.getMessage(), eee);
            }

            if (lostMessages != null && lostMessages.size() > 0)
                notifyMessageLost(lostMessages);

            _excuting = false;
        }
    }

    protected void notifyMessageLost(ArrayList<Protocal> lostMessages) {
        if (serverLauncher != null && serverLauncher.getServerMessageQoSEventListener() != null)
            serverLauncher.getServerMessageQoSEventListener().messagesLost(lostMessages);
    }

    public QoS4SendDaemonRoot startup(boolean immediately) {
        stop();

        timer = new Timer();
        timer.scheduleAtFixedRate(new TimerTask() {
                                      @Override
                                      public void run() {
                                          doTaskOnece();
                                      }
                                  }
                , immediately ? 0 : CHECH_INTERVAL
                , CHECH_INTERVAL);

        logger.debug("【IMCORE" + this.debugTag + "】【QoS发送方】====== 消息发送质量保证线程已成功启动");

        return this;
    }

    public void stop() {
        if (timer != null) {
            try {
                timer.cancel();
            } finally {
                timer = null;
            }
        }
    }

    public boolean isRunning() {
        return timer != null;
    }

    public boolean exist(String fingerPrint) {
        return sentMessages.get(fingerPrint) != null;
    }

    public void put(Protocal p) {
        if (p == null) {
            if (DEBUG)
                logger.warn(this.debugTag + "Invalid arg p==null.");
            return;
        }
        if (p.getFp() == null) {
            if (DEBUG)
                logger.warn(this.debugTag + "Invalid arg p.getFp() == null.");
            return;
        }

        if (!p.isQoS()) {
            if (DEBUG)
                logger.warn(this.debugTag + "This protocal is not QoS pkg, ignore it!");
            return;
        }

        if (sentMessages.get(p.getFp()) != null) {
            if (DEBUG)
                logger.warn("【IMCORE" + this.debugTag + "】【QoS发送方】指纹为" + p.getFp() + "的消息已经放入了发送质量保证队列，该消息为何会重复？（生成的指纹码重复？还是重复put？）");
        }

        sentMessages.put(p.getFp(), p);
        sendMessagesTimestamp.put(p.getFp(), System.currentTimeMillis());
    }

    public void remove(final String fingerPrint) {
        try {
            // remove it
            sendMessagesTimestamp.remove(fingerPrint);
            Object result = sentMessages.remove(fingerPrint);
            if (DEBUG)
                logger.warn("【IMCORE" + this.debugTag + "】【QoS发送方】指纹为" + fingerPrint + "的消息已成功从发送质量保证队列中移除(可能是收到接收方的应答也可能是达到了重传的次数上限)，重试次数="
                        + (result != null ? ((Protocal) result).getRetryCount() : "none呵呵."));
        } catch (Exception e) {
            if (DEBUG)
                logger.warn("【IMCORE" + this.debugTag + "】【QoS发送方】remove(fingerPrint)时出错了：", e);
        }
    }

    public int size() {
        return sentMessages.size();
    }

    public void setServerLauncher(ServerLauncher serverLauncher) {
        this.serverLauncher = serverLauncher;
    }

    public boolean isDebugable() {
        return this.DEBUG;
    }

    public QoS4SendDaemonRoot setDebugable(boolean debugable) {
        this.DEBUG = debugable;
        return this;
    }
}
